-LRB- CNN -RRB- -- Los Angeles police have launched an internal investigation to determine who leaked a picture that appears to show a bruised and battered Rihanna .

Rihanna was allegedly attacked by her boyfriend , singer Chris Brown , before the Grammys on February 8 .

The close-up photo -- showing a woman with contusions on her forehead and below her eyes , and cuts on her lip -- was published on the entertainment Web site TMZ Thursday . TMZ said it was a photo of Rihanna .

Twenty-one-year-old Rihanna was allegedly attacked by her boyfriend , singer Chris Brown , on a Los Angeles street before the two were to perform at the Grammys on February 8 .

`` The unauthorized release of a domestic violence photograph immediately generated an internal investigation , '' an L.A. police spokesman said in a statement . `` The Los Angeles Police Department takes seriously its duty to maintain the confidentiality of victims of domestic violence . A violation of this type is considered serious misconduct , with penalties up to and including termination . ''

A spokeswoman for Rihanna declined to comment .

The chief investigator in the case had told CNN earlier that authorities had tried to guard against leaks . Detective Deshon Andrews said he had kept the case file closely guarded and that no copies had been made of the original photos and documents .

Brown was arrested on February 8 in connection with the case and and booked on suspicion of making criminal threats .

Authorities are trying to determine whether Brown should face domestic violence-related charges .

Brown apologized for the incident this week .

`` Words can not begin to express how sorry and saddened I am over what transpired , '' the 19-year-old said in a statement released by his spokesman . `` I am seeking the counseling of my pastor , my mother and other loved ones and I am committed , with God 's help , to emerging a better person . ''

CNN 's Brittany Kaplan contributed to this report .

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Los Angeles police investigating leak of photo of a battered woman

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TMZ Web site says photo is of R&B singer Rihanna

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Rihanna allegedly attacked by her boyfriend , singer Chris Brown , on February 8

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The two were scheduled to perform at the Grammys